Could you explain the solution step by step

Question 3 (20 pts) The device shown in the sketch is developed to measure the hydrostatic force on the flat face of the circular-arc block and compare it with the theoretical value for given depth h. The counterweight is arranged so that the pivot arm is horizontal when the block is not submerged, hence the weight W can be correlated with the hydrostatic force when the submerged arm is again brought to horizontal. (a) (10 pts) ketch the hydrostatic pressure distribution on the submerged arc block (both on curved and flat surfaces). Make your sketch clear. Be careful with the length and the direction of the arrows. Then draw the free-body diagram of the pivot arm combined with the circular-arc block to show all relevant forces. Explain how, in principle, the device should work. (b) (10 pts) Derive a formula for W as a function of h in terms of the given parameters. Question 4. (25 pts) A 1-m-diameter cylindrical mass, M, is connected to a 2-m wide rectangular gate as shown in figure. The gate is to open when the water level, h, drops below 2.5m. Neglect friction at the gate hinge and pulley. (a) (5 pts) Sketch the pressure distribution on the gate. Ignore atmospheric pressure as it applies on both sides of the gate. (b) (10 pts) Determine the magnitude, point of application and direction of the resultant hydrostatic force on the gate when it is about to open. (c) (10 pts) Determine the required value of M for the gate to open when h=2.5m